Propeller



May 3o, 1933. T R MECMECHEN 1,911,376

PROPELLER Original Filed May 16, 1929 3 Sheets-Sheet 1 May 30, 1933. T R MacMECHEN 1,911,376

PROPELLER Original Filed May 16, 1929 3 Sheets-Sheet ,2

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May 30, 1933. T. R. MacMEcHl-:N A1,911,376

PROPELLER original Filed May 1e', 1929 :s sheets-sheet s 16 I1/minuto :2v/wma; aclcen,

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Patented May 30, 1933 UNITED As'rirrffas THOMAS a. MACMECHEN, OF NEW YORK, n. Y.

PROPELLER VApplication filed May 16, 1929, Serial This invention relates generally to means designated propellers or fans, while it has more particular reference to devices adapted to set up a reaction between arotating body and the element inwhich it operates.

More specifically propellers or fans, whether used in air or liquid, embody blades usually radiating relative to the axis of rotation and decreasing in Said axis to their tips.

With propellers now in common use the air, gas or liquid acted upon is disturbed in Y its rotational aspect but very little, while the blades are generally shaped to slip7 or pass through the medium with a minimum resistance around the axis of rotation; and, consequently, there exists a pronounced reactive thrust or negative power influence with resultant loss in efficiency.

2o A general object of this invention is to provide a device of the noted character which radically departs from all -known types of propellers or fans in that it is of unusual set up and function; or, in other words, my novel propeller or fan deviates entirely from prevailing constructions and is product-ive of a markedly effective manner of functioning, irrespective of the medium in which it operates.

Another object of this invention is to provide a propeller or fan in which the blades are disposed equi-angularly and off-center so as to increase and utilize the two pronounced and complementary forces, centrifugal and propulsive; or, in other words, the blades are located and adapted so that, when in operation, their effect is to rotative- K ly-hold or cling to the medium before the final kick, Incidentally it may be here 4oY noted that a much greater' reactive effect or kiclr is attainable when operating on `air in motion, than when operating instill air. v

A further object of this invention is to provide a propeller or fan characterized by serial or multiple equi-angularly disposed relatively-overlapping `inter-connected blades, said blades having their major dimension tangentially ldirected in the plane pitch angle from No. 363,459. Renewed Marche, 1933.

A still further object iste-provide ajpropeller or fan of the typified character. ernbodying non-contactingl blades with 'respect to the hub, each saidblade constitutinga tangentially directed entity with referencef55 1 to the axis of rotation and the series being equi-angularly disposed with regard to each Y other. l `i With the foregoing and lothenobjects in view, and in order that the various aspectsifdo of myinvention may be appreciated,as well as its points of superiority over-proir art fully comprehended typical :embodiments thereof will now be described vin conjunction withv theaccompanying drawings. F

Fig. 1 is an end viewof a practicalffembodiment of this invention as adaptedmore particularly, although vnot essentially, `for faeronautical usage. y ,A

Fig. 2 is a plan view, looking downwardly?- 70 from above Fig. 1.

:Fig 3 is a somewhat enlarged sectional detail, as viewed inthe directiony of the arcuate arrows 3-3 on Fig. Vl. i

Fig. 4 is anend view of a modified form-`75 vof my novel propeller "or fan embodying means whereby the screw pitch maybe `adjustably varied. l

Fig. 5 is a side view lookingitoward the left hand of the preceding illustration.r 1 e30 Fig. 6 is an elevational view in reverse with .respect to Fig. et. 1 Fig. 7is a sectional view, taken-.approximately on the plane designated 7"-7 inF-ig.V 4, but drawn to a larger scale. Fig. 8is1ar`85 sectional view, taken on the pla-ne marked 8 8 in Fig. 4. Fig. 9 is an end view vof a further'form of my novel propeller orl fan.

Fig. 10 is a view looking downwardlym from above the preceding illustration. Y

Fig. 1l is a fragmentary edge view illustrative of a'convenient manner'of shaping the Amedial portionof the propeller blades, per se, for supporting-connection angular-W5 ly-offset relative to theaXis Vof rotation.; and,

Fig. 12 is a face view thereof, or'flook- 'ing upwardly relative'to Fig.l1l.

In all the views like partsaredesignate'd by the same reference symbols, while those-T5100 components varying in essential characteristics have distinguishing suffices so as to avoid conflict in description.

Referring firstly to Figs. 1 to 3 inclusive, which exemplify a typical embodiment of the novel principles involved in this invention, and illustrate a propeller useful for operation in air or gas, the numeral 13 designates the tail of the propeller shaft, and.

14 the hub thereof that is provided with three (for example only) radially-directed olf-center arms `15 that constitute supporting media for the blades 16. As will be seen I conveniently, although not essentially, utilize three blades 16 disposed at approximately 120 to each other with their outer portions intersecting or crossing one an.- other in spacial relation; so that as one blade 16V is pushing the air or gas with a cupping or holdingv action and setting up a vortex motion, the following blade or blades 16 pick up such action without diminution and impart an augmented kick thereto. In

.other-words, it will be noted, I aim in a measure to confine all the vortex within the f field of rotation of the propeller, and there- Yby greatly increase the reaction between the blades 16 and the air vortex thus created, which is equivalent to materially augmenting the density lof the air and thereby `introducing a new multiplying coeflicient for propeller data. The effect of this new coeflicient in propeller data. may be comparable to stored energy, but it is not asserted as a method of getting something out of nothing, but rather a novel manner of sacrilicing a small amount of energy to establish eration, each said blade is attached medial-- 'ly of its major dimension by means, such as rivets or bolts 17, to the foresaid hub arms 14; as well as being suitably shaped to provide fianking substantially-,paralleling flares 18 which sharply merge into their junction with said arms and taperingly sweep outwards in the direction of rotation. These blades 16 are configured to, also, have their greatest area in the plane of rotation .with hyperbolic curvatures 19 throughout a portion of the following edges of their tips 20 inwards, such curvatures being determinative of the pitch, and said blades being never set in excess of twenty-two-anda-half degrees (221/20) relative to the axis of the hub 14. A further feature noticeable,

cumferential path, relative to the kaxis of the hub 14, with their opposed edges 22 merging into the leading and trailing edges of the blades 16. Conveniently the fins 21 may be provided with appropriate fastening means 23 whereby they are secured to the blades 16, or they may be otherwise rigidly connected to said blades in any of the well known andi obvious manners; while said curvatures 24' where their following edges merge into the larms 15.

Referring now to Figs. all those parts corresponding with the preceding description are similarly designated by like reference symbols, with thesuliix a; and7 for the avoidance of repetitive explana-` tion, I will herein only point out the distinguishing features thereover. In this conneetion, it is to be observed that I dispense with the arcuate fins 21 and in lieu thereof make use of connectors 25 having capacityY tive on a somewhat larger scale of the flares 18 hereinbefore referred to in connection with Figs. yll-S. It is also to be' seen that the blades 16?) have somewhat equiform. tips, that is to say,.they are curved at their terminal edges 26 to follow a circumferentiah path relative to the axis of the hub 14.

The typified forms above described are simply by way of illustrating convenient examples of what may be termed a rotative triangular arrangement of the blades 16,2

16a, and 16o, with their respective axes in the same plane or disposed at an angle from the plane of rotation; and, obviously it will be readily. understoodthat while such triangular dis ositions have been found ex-L ceedingly e ective and strong under extensive tests, any multiple thereof may be equally well adopted in paralleling-tangential or diverging-radial relation.

Furthermore, while I have shown and lf-8 inclusive,

Lblades are reduced laterally by opposing Y outlined certain practical embodiments of my invention, it is to be clearly understood the same are purely illustrative, as the fundamentals thereof may be otherwise embodied without departing from the spirit and scope of my said invention as defined in the appended claims; and by which it is intended to reserve all novelty inherent as broadly as possible.

Having thus set forth my invention what I claim, is

1. A propeller characterized by blades obliquely superposed relative to each other, with their outer portions intersecting and with their greatest dimension angularly disposed in the field of rotation, and fins overlappingly connecting said blades in spaced relation in their intersecting region of their ti s.

p2. A propeller characterized by blades offset relative to the hub and to each other having their greatest dimension angularly disposed within the zone of rotation radially directed arms connected medially of the major dimension of said blades, fins following a circumferential path relative to the axis of rotation, and rigidly connecting said blades intermediate the hub and their tips, and said ns having opposed edges merging into the leading and trailing edges of the blades.

3. A propeller characterized by blades offset relative to the hub and having their greatest dimension in its particular plane of rotation, each said blade embodying opposing flaresat their medial portion and region of support away from the hub.

4. A screw propeller comprising angularly disposed relatively-overlapping and spaced inter-connected blades, offset from a hub, each of said blades being tangentially directed in the plane of rotation and having the medial portion thereof connected in spaced relation to said hub.

5. A screw propeller comprising angularly disposed relatively overlapping and spaced inter-connected blades, offset from a hub, each of said blades being tangentially directed in the plane of rotation and having the medial portion thereof connected in spaced relation to said hub, said blades be-v ing supported free of contact with the axis of rotation and each blade embodying an essentially composite pitch, one component being at an angle to a particular plane of rotation and the other being angularly disposed to a predetermined radius.

6. A screw propeller comprising spaced interconnected blades obliquely superposed in the region of their tips and being offset from the hub with the greatest dimension angularly disposed to a plane of rotation, said blades being supported free of contact with the axis of rotation and each blade embodying an essentially composite pitch,

one component being at an angle to a particular plane of rotation and the other being angularly disposed to a predetermined radius.

7. A screw propeller comprising angularly disposed and 'relatively-overlapping` blades offset from the hub, each of said blades being tangentially directed in the plane of rotation and having the medial portion thereof connected in spaced relation to said hub, and fins interconnecting said blades, said fins following a circumferential path relative to the axis of rotation and rigidly connecting said blades intermediate the hub and their tips, said fins also having opposed edges merging into the leading and trailing edges of the blades.

8. A screw propeller comprising angularly disposed relatively overlapping and spaced inter-connected blades, offset from a hub, each of said blades being tangentially directed in the plane of rotationand having the medial portion thereof Yconnected in spaced relation to said hub, each of said blades embodying opposing flares at said medial portion and region of support away from said hub, the greatest dimension of the blades being in the particular plane of rotation thereof.

In testimony whereof I aflix my signature at Philadelphia, Pennsylvania, U. S. A., this 13th day of May, 1929.

THOMAS R. MACMECHEN. 

